Question

Calcium is obtained industrially by electrolysis of molten CaCl2 and is used in aluminum alloys. How many coulombs are needed to produce 19.2 g of Ca metal? If a cell runs at 15 A, how many minutes will it take to produce 19.2 g of Ca(s)?

Answer 1

Step-by-step explanation:

The given data is as follows.

m = 19.2 g, I = 15 A

The given reaction equation will be as follows.

`CaCl_(2) \rightarrow Ca^(2+) + 2Cl^(-)`

`Ca(s) \rightarrow Ca^(2+) + 2e^(-)`

As, 1 mole will give
`2 * 96500 C` of charge. So, calculate the amount of charge deposited by 19.2 g as follows.

`2 * 96500 C * (19.6 g)/(40.07 g/mol)`

= 94404.791 C

Hence, 94404.791 C are needed to produce 19.2 g of Ca metal.

Therefore for 15 A, minutes required to produce 94404.791 C and 19.2 g of Ca(s) will be calculated as follows.

=
`94404.791 C * (1 Amp sec)/(1 C) * (1)/(15 Amp) * (1 min)/(60 sec)`

= 104.9 mins

Thus, we can conclude that 104.9 minutes are required if a cell runs at 15 A, how many minutes will it take to produce 19.2 g of Ca(s).